A former FBI agent was sentenced yesterday to one year of probation for illegally accessing bureau computers to help high-profile Los Angeles private investigator Anthony Pellicano in his trial on wiretapping and racketeering charges.

Mark T. Rossini, 47, told U.S. Magistrate Judge John M. Facciola in the District's federal court that he was "so profoundly and deeply ashamed and remorseful" for his conduct. Facciola also ordered Rossini, who was an FBI agent for 17 years, to pay a $5,000 fine.

The former agent pleaded guilty in December to illegally searching bureau computers for personal purposes. As part of the plea deal, he agreed to resign from the FBI. Most of those searches were related to the Pellicano case, federal prosecutors said.

At the time he conducted those illegal searches, Rossini was dating the actress Linda Fiorentino, known for her role in "The Last Seduction." Fiorentino had a previous relationship with Pellicano and wanted to help him, law enforcement officials have said.

Assistant U.S. Attorney Tejpal S. Chawla wrote in court papers that in January 2007 Rossini gave a report about the Pellicano case to a person identified by Chawla in court records as "X." Law enforcement sources have identified "X" as Fiorentino, and have said she gave the report to an attorney for Pellicano, who used the report to accuse prosecutors of withholding evidence from the defense team.

Rossini is living in New Orleans, said his attorney, Adam Hoffinger.

Pellicano was sentenced in December to 15 years in prison after being convicted of conspiring to run a criminal enterprise that employed illegal wiretaps to dig up dirt on the rich and famous on behalf of his elite Hollywood clients.